Recovery of Residual Brewer’s Yeast by Electroactivation

Yeasts resulting from the brewing process (RBY) are a valuable by-product, with an important content of minerals, vitamins and, especially, proteins. The purpose of the research was the electroactivation of RBY and the simultaneous obtaining of two products—protein concentrates and hydrolyzed protein from residual brewer’s yeast. Electroactivation is a non-residual process, without the use of chemical reagents and relatively inexpensive. The variation of the electroactivation conditions allowed the separation of 90% - 94% of the proteins in the form of protein concentrates. During the process, it is attested to increase the pH value and decrease the redox potential, which characterizes the multiple redox processes that take place in the cathode cell, including sedimentation at the isoelectric point. The presence of albumin in the protein fractions of RBY allows the formation of protein complexes with calcium, attributing a higher biological value to the obtained products.

The Economic Potential of Brewer’s Spent Grain (BSG) as a Biomass Feedstock

This paper analyzes a pro-forma economic market and supply chain system for the reuse of a lignocellulose (brewer’s spent grain) in an industrial biotechnology environment. An extant literature review was conducted, followed by a technical analysis of BSG, and the development of a supply chain system and economic market analysis based upon a participant brewing company and industry experts. In this paper, it was found that, even with the potential for future improvements in the conversion of brewer’s spent grain (BSG) from an efficiency standpoint, this industrial residual is supply chain prohibitive as a biofeedstock in comparison to other lignocellulose materials, therefore, centralized market relationships would not be advantageous for sellers and buyers. Future research should consider the viability of centralized supply chain structures for alternatives that may exist as future bio-feedstocks.

富铬酵母中14种元素的ICP-AES测定

本文用ＩＣＰ－ＡＥＳ法同时测定富铬酵母中Ｋ、Ｆｅ、Ｐ、Ｚｎ、Ｃｒ、Ｃｕ、Ｍｎ、Ｃｏ、Ｂａ、Ｓｒ、Ｖ、Ｎａ、Ｍｇ、Ｃａ１４种元素的含量。结果表明，富铬酵母中的铬对其他元素的浓度有一定影响，并且，Ｋ、Ｍｎ、Ｐ、Ｖ、Ｍｇ、Ｃａ的浓度明显低于普通酵母。

Effect of Fish Meal Replacement by Unconventional Meal in the Post-Larval Diet of Clarias Gariepinus in Benin (West Africa)

To reduce the pressure on aquatic resources due to the use of fishmeal in fish feed, the mastery and use of alternative sources of fishmeal in all stages of fish development are essential. Five diets including 4 experimental and one control diet were considered. Experimental diets of post-larvae were developed from unconventional ingredients in which fishmeal was completely replaced by a mixture of brewer’s yeast, chicken viscera and maggots. These foods were tested on Clarias gariepinus post-larvae with an initial average weight of 80 ± 1 mg. 1500 fish individuals were equally distributed in 15 concrete basins with a volume of 500 L forming five treatments in triplicate. Fish individuals were fed, manually at a ration rate of 20%, four times per day. The specific growth rates were 8.38%/day in imported food and 6.35%/day in the experimental food receiving 45.5% of protein from unconventional meal. Similar results were obtained with the feed consumption index. These encouraging results show that it is possible to partially or completely replace fishmeal in catfish feed and obtain an economically profitable production. The recovery of waste such as chicken viscera, brewer’s yeast and soybean meal in fish food formulation as tested in this study is a good contribution to environmental sanitation.

Acute Toxicity and Antipyretic Activities of a Methanolic Extract of Alchornea cordifolia Leaves

Alchornea cordifolia (Euphorbiaceae) is a very prized plant among traditional healers in Africa. Its leaves are used for its antipyretic properties in traditional areas. The aim of our study is to determine the acute toxicity and the antipyretic activity of a methanolic extract of Alchornea cordifolia leaves. Acute toxicity was assessed by measuring mortality, changes in body weight, spontaneous movements, and normal rectal temperature in mice. Antipyretic activity was evaluated by brewer’s yeast-induced hyperpyrexia in rats according to Teotino method (1963). The antipyretic effect of methanolicextract of Alchornea cordifolia leaves was compared with paracetamol (100 mg/kg bw) orally. Groups of mice treated with doses of 6500;3250;1625 and 812.5mg/kg of the extract did not show any mortality, nor significant alteration of body weight, nor alteration of spontaneous movements. However, incomplete reversed dose-dependent hypothermic activity was observed with doses of 50.78;101.56;203.12;406.25;and 812.5 mg/kg p.o. of the extract, showing acute toxicity of this plant. In the antipyretic assay, the extract with doses of 50.78;101.56;203.12;406.25;and 812.5 mg/kg p.o. exhibited a significant dose-dependent antipyretic activity similar to paracetamol (100 mg/kg bw) in rats. Thus Alchornea cordifolia may inhibit prostaglandins-biosynthesis from hypothalamus. Our results support claims on its traditional uses in management of fever. However Alchornea cordifolia may affect hypothalamus not only during fever but also when body temperature is normal.

发酵啤酒糟对蛋鸡生产性能、蛋品质、免疫功能和肠道消化酶活性的影响

为了探讨发酵啤酒糟对蛋鸡生产性能、蛋品质、免疫功能和肠道消化酶活性的影响,把3 840只44周龄的蛋鸡随机分为4个饲粮处理组,每组4个重复,每个重复240只蛋鸡,各组分别饲喂含0、2%、4%、7%发酵啤酒糟(FBSG)的饲粮。结果表明:与对照组相比,饲喂2周后,2%FBSG组的蛋重增加,但未达到显著水平(P>0.05),料蛋比显著降低(P<0.05),4%FBSG组的蛋鸡生产性能和蛋品质没有显著变化(P>0.05),7%FBSG组的产蛋率和料蛋比均显著降低(P<0.05);饲喂4周后,2%、4%、7%FBSG组的蛋鸡生产性能和蛋品质均无显著变化(P>0.05),但蛋鸡血清免疫球蛋白水平和十二指肠淀粉酶及脂肪酶活性显著增加(P<0.05),蛋鸡血清内毒素水平显著降低(P<0.05)。说明蛋鸡饲粮中FBSG的使用量不超过4%时,对蛋鸡生产性能无明显不利影响,对蛋鸡免疫功能和肠道健康有一定改善作用。

单螺杆挤压对啤酒糟中水溶性膳食纤维含量影响的研究

通过挤压膨化技术对啤酒糟进行预处理,研究单螺杆挤压加工对啤酒糟中水溶性膳食纤维(water-soluble dietary fiber,SDF)含量的影响。试验采用正交试验优化啤酒糟挤压工艺,以提高啤酒糟中SDF的含量。在单因素试验基础上,以啤酒糟的水分含量、挤压机的机筒温度和螺杆转速为自变量,SDF含量为指标,确定最佳工艺参数。结果表明:水分含量20%,机筒温度130℃以及螺杆转速150 r/min,在此条件下测得的挤压啤酒糟SDF含量与原啤酒糟相比提高了24.00%。挤压膨化可以提高啤酒糟中水溶性膳食纤维含量。

Fluid dynamics analysis and pyrolysis of brewer’s spent grain in a spouted bed reactor

Brewer’s spent grain (BSG) is a large-scale agroindustrial waste that could be more efficiently utilized. This waste is composed of lignocellulosic material and so may serve as a good source of biomass for thermochemical conversion. The present study investigated the fluid dynamics behavior of mixtures of sand and BSG in a spouted bed to assess the viability of the thermochemical conversion of this biomass via fast pyrolysis. Fluid dynamics analyses were performed while varying the mass fraction of BSG (6–80%) and the static bed height (6.6–13.4 cm). Empirical equations for predicting the minimum spouting conditions and the mixing index were obtained using a regression technique, and the selected fluid dynamics parameters were employed in the spouted bed pyrolysis. The bio-oil resulting from this process was rich in phenolic compounds, various nitrogenated compounds (representing precursors for pharmaceuticals) and long-chain hydrocarbons. The products obtained from the analytical and spouted bed pyrolysis processes were also compared.

利用啤酒废酵母间歇发酵合成谷胱甘肽的研究

研究利用啤酒废酵母生产谷胱甘肽的目的是降低谷胱甘肽生产成本、提高啤酒废酵母附加值.研究考察了在2升通气搅拌罐中通气量、搅拌速度、初始葡萄糖浓度以及废酵母加入量对谷胱甘肽合成的影响.实验表明,好氧活化可以显著提高酵母细胞内的谷胱甘肽含量.由于啤酒废酵母的添加量较大,使得反应液中菌体浓度较高,发酵过程中保持较大的通气量和搅拌速率有利于提高细胞活性和促进谷胱甘肽的积累.通过实验确定了2L发酵罐中较佳的操作参数为搅拌速度500r@min-1,通气量6 L@L-1@min-1.过高的初始葡萄糖浓度对谷胱甘肽的合成有一定的抑制作用,比较合适的初始葡萄糖用量为加入的废酵母湿重的10%.废酵母加入量增大会导致胞内谷胱甘肽含量下降,但由于细胞干重的大幅度增加,在实验范围内,最终单位反应器体积的谷胱甘肽产量则随废酵母加入量增大而增大.实验表明,废酵母加入量在湿酵母为100～300g@L-1之间是合适的.

富铬酵母降低糖尿病大鼠血糖的生物效应评价

目的 : 研究富铬酵母对四氧嘧啶致实验性糖尿病大鼠的降血糖作用。方法 : 对糖尿病大鼠连续口服富铬酵母〔 Cr 2 0 0μg/ (kg bw· d)〕和〔 Cr 2 0μg/ (kg bw· d)〕以及普通酵母〔 Cr 1μg/ (kg bw· d)〕4w,观察记录每天的饮水和进食情况。每周末采集尾静脉血 ,测定血糖、总胆固醇 (TC)、甘油三酯 (TG)、低密度脂蛋白 (LDL)、高密度脂蛋白 (HDL )、胰岛素、C肽的含量。结果 : 各治疗组大鼠的体重明显高于糖尿病组 ,各治疗组大鼠的血糖水平、TG、TC、LDL、胰岛素及 C肽显著降低 ,而 HDL升高。高剂量富铬酵母的降血糖作用明显高于其他各组。结论 : 富铬酵母在体内可以改善糖和脂代谢 ,可用来预防和治疗糖尿病。

啤酒糟在国内外食品加工中的利用现状

啤酒糟是啤酒酿造的最主要副产物,含有丰富的蛋白质和非淀粉多糖。随着啤酒原料中小麦芽使用量的增加(≥40%),啤酒糟中膳食纤维和蛋白质的含量明显增加。目前啤酒糟主要用作饲料或工业原料出售,但在食品加工中的应用研究较少。本文通过概述啤酒糟的营养、加工处理方法及其在国内外食品加工领域中的研究利用情况,为高蛋白膳食纤维啤酒糟食品的进一步开发提供了参考。

废啤酒酵母综合利用研究进展

从酵母的营养与有效成分入手,全面回顾了近年来国内外利用废啤酒酵母开发食用营养酵母、分离蛋白、肽、氨基酸等新蛋白资源产品,生产酵母抽提物功能性调味品,以及提取β-葡聚糖、甘露聚糖、海藻糖、SOD、谷胱甘肽等功能活性物质方面的研究动态和进展,阐述了对废啤酒酵母资源综合利用的重要性。

蛋白酶水解啤酒糟蛋白动力学研究

为了研究蛋白酶水解啤酒糟蛋白的动力学性质,采用pH-stat法,以蛋白酶对啤酒糟中提取的蛋白进行水解处理。探讨了底物浓度[S]、酶与底物浓度比[E]/[S]和反应时间t对产物水解度DH的影响。建立了[S]及t同DH间的数学模型。通过不同底物浓度加碱量随水解时间的变化速度,测定出蛋白酶水解啤酒糟蛋白的K值。

啤酒糟发酵应用

啤酒糟是微生物发酵的良好基质,利用微生物发酵啤酒糟的用途非常广泛。啤酒糟的再利用,有利于保护生态环境和节约资源。综述了近年来国内外啤酒糟在酶制剂、动物饲料、活性物质、食品添加剂方面的发酵应用。

利用啤酒糟制备高品质饲料蛋白

通过刀片粉碎和筛分技术对啤酒糟进行预处理,对筛下物进行球磨处理、固态酶解和有益微生物发酵,可以显著提高啤酒糟的饲用品质,制备高品质饲料蛋白。啤酒糟经刀片粉碎后过60目筛,筛下物粗蛋白含量达到38.8%,粗纤维含量降低到1.89%,实现蛋白-纤维的初步富集分离。对筛下物球磨后,经纤维素酶、木聚糖酶和蛋白酶混合固态酶解和产朊假丝酵母JX-09固态发酵之后,其粗蛋白含量达到45.17%,比啤酒糟原样提高了59.6%,多肽含量从0.68%提高到5.21%,蛋白体外消化率从53.7%提高到61.8%,水解氨基酸总量达到42.18%,比啤酒糟原样提高了60%,必需氨基酸总量达到17.3%,比啤酒糟原样提高了60%,粗纤维含量达到1.66%,比啤酒糟原样降低了89%。

粉碎及酶处理对啤酒糟理化特性的影响

对啤酒糟进行机械预处理可以改变啤酒糟的物理结构，使得抗营养因子更容易降解，提高其生物利用率，改善饲用品质。采用球磨和刀片式粉碎预处理酒糟，粒径分布分别在300～1000μm和10—200μm。经球磨和刀片粉碎后的啤酒糟可溶性总糖含量分别提高了2．2倍和1．7倍，还原糖含量分别提高了40％和18．9％。球磨和刀片粉碎后的啤酒糟经纤维素酶、中性蛋白酶分别酶解后，可溶性总糖含量比啤酒糟原样经酶解后分别提高了2．5倍和1．7倍，还原糖含量分别提高了2．2倍和1．4倍，水溶性蛋白含量分别提高了1．8倍和1．4倍，多肽含量分别提高了2．2倍和1．2倍。经球磨后的啤酒糟酶解效率高于经刀片粉碎的啤酒糟，刀片粉碎并筛分可以初步实现蛋白-纤维的富集分离。

一种新型蛋白质混凝土发泡剂的研制及性能研究

以啤酒废酵母为原材料,制备一种新型的蛋白质混凝土发泡剂并通过正交实验对水解条件进行优化。研究了发泡剂以及不同添加剂对其发泡性能和泡沫稳定性的影响,结果表明表面张力是发泡剂发泡性能提升的重要因素,但对泡沫稳定性没有决定性影响;适当增加溶液黏度可延长其泡沫稳定时间,其中添加卡拉胶0.1%/100 mL发泡液时,发泡体积为725 mL,其泡沫稳定时间也超过了25 h。

富铬酵母的各种元素和氨基酸分析

铬作为人和动物体内的必需微量元素，在体内与蛋白质、核酸以及各种低分子量配体相结合，参与机体的正常糖、脂代谢，促进人体的生长发育。一些研究表明，铬的生物化学作用主要是胰岛素的增强剂，对人体内的糖代谢起到了一定的生物效应，可以降低糖尿病病人的血糖、血脂和...

机械破壁和盐法结合从啤酒酵母中提取RNA

机械破壁法和盐法结合 ,在酵母浓度为 10 % ,高压均质破壁循环两次 ,盐浓度 5 % ,95℃下加热 3h ,RNA平均净得率 >3% ;将上清液回收利用 ,回用到第三次时 ,RNA净得率达 3.6 7%。

酶解机械预处理啤酒糟制备饲用蛋白肽

啤酒糟经过粉碎后筛分,筛下物经球磨后粗蛋白含量提高到38.8%,比原样提高了36.1%,水溶性蛋白含量提高到2.53%,比原样提高了3.1倍,经中性蛋白酶液态酶解,水溶性蛋白含量达到12.85%,比原样的7.88%提高了1.6倍,机械预处理显著提高了酶解效率。通过单因素实验和混合水平均匀设计实验,确定了啤酒糟最优酶解条件:加酶量2 400 U/g,酶解温度45℃,酶解pH 8.0,酶解时间8 h,此时水溶性蛋白含量能够达到21.31%,提取率达到54.9%。对酶解液进行真空冷冻干燥,制备饲用蛋白肽,粗蛋白含量达到78.8%,氨基酸含量达到74.6%,必需氨基酸含量达到28.18%,多肽含量达到60.8%。